<script>
// This function takes a Node n, replaces it in the tree with an Element node
// that represents an HTML <b> tag, and then makes the original node the
// child of the new <b> element.
function embolden(n) {
    if (typeof n == "string") n = document.getElementById(n); // Lookup node
    var b = document.createElement("b"); // Create a new <b> element
    var parent = n.parentNode;           // Get the parent of the node
    parent.replaceChild(b, n);           // Replace the node with the <b> tag
    b.appendChild(n);                    // Make the node a child of the <b>
}
</script>

<!-- A couple of sample paragraphs -->
<p id="p1">This <i>is</i> paragraph #1.</p>
<p id="p2">This <i>is</i> paragraph #2.</p>

<!-- A button that invokes the embolden() function on the element named p1 -->
<button onclick="embolden('p1');">Embolden</button>
